Double-click the left mouse button anywhere on the map and sweep across the map to
color districts (assigning them to the selected CD).

Double-click again to stop coloring.

Hover over the map to show demographic data for individual
voting districts.

Use the check boxes in the Show section to hide or show county, city or
old CD boundaries and labels, or new CD labels. All labels can be moved and
resized.

Use the Old/New CD check box to show the old and
new CD boundaries for the selected CD only.

Use the File menu and click Save Asto save your work.

When you are close to assigning all districts to some CD, use the Next
Unassigned button to find districts not assigned to any district.
You can also use Find CD Parts to locate districts
you may have inadvertently left isolated.

Use the Area Views section to create views of
zoomed in areas; areas views are recorded with the current Show choices at the time
they are created. Each area view can be written as a JPEG, but the Bing map
background cannot be included.

How It Works

The application is a Silverlight 4.0 control running in an ASP page in your
browser. When you select a state, the app calls a web service that downloads all
of the data you need for that state. Once the app has obtained the data, it never
goes back to the server. Also, the app will cache the data on your machine so
that you'll get going faster the next time you work on the state. The data includes:

All of the data, except partisan data and custom shapes/data available
for a few states, comes from the U.S.
Census Bureau.

Note: A block group is a census
designation that is a group of up to 4 census blocks. A census block is the
smallest area used by the census bureau. Blocks and block groups do not exactly
correspond to voting districts or precincts. A voting district
is a designation determined by each state. All but a few states have given
voting district information to the Census Bureau and the Bureau has computed
statistics for those areas. In my application, some states now use voting
districts; others still use block groups; and for some I provide both. The size
of voting districts appear to vary considerably between states. For some states
(e.g. Maryland) I find it harder to get the CDs to have nearly equivalent
population, because the voting districts are so populous. For others, they appear
very close in size to block groups. For conciseness, in this Help file I
will use district to mean block group or voting district.

Note: The polygons and data for states are large and
therefore will take time to download. For you techies, to get the polygons, I
started with ShapeFiles (.SHP) from the Census Bureau's website. They can be
pretty large, so I created my own custom file format (.DSH) that is about 1/4
the size.

Using the Map

The map shapes are layered on top of a Bing™ map. You pan and zoom just
like any map, using the pan and zoom controls or holding the left mouse button
on the map and dragging. You can also switch between the road map, aerial
map and a blank map.

Left Control Panel

The left side of the application view has a control
panel.

Coloring On/Off and Zoom Level

The Zoom Level indicator tells you what
zoom level you are currently at.

In Version 2.0.4 there are two ways to color. You can switch between
them with a check box on the File Menu.

Old Way

A green box that indicates whether coloring
is on or off. Coloring On means that as you
sweep the mouse across the map (whether or not you hold the mouse button
down), the districts will be assigned to the current CD
(and thus given that CD's color). You turn coloring
on or off by double-clicking anywhere on the map.

New Way

The green box is a button labeled "Color
Districts." Click the button or double-click on the map to turn
coloring on. When coloring is on, the
button is labeled "Done Coloring." Hold the mouse button down
and sweep the mouse across the map to color districts.

You can
also hold down the Ctrl key and the mouse button and move the
mouse (called Ctrl-Drag) to draw a box on the map.

When you
release the mouse button all the districts in the box will be
colored. Click "Done Coloring" or double-click the map to turn
coloring off.

Number of CDs

The number of CDs is controlled by the #CDs slider.
You can slide the control or use the control's arrows to change the number of CDs you want
for your state. Beware: When you change
the number of CDs, any districts you have already assigned are cleared. You can
create up to 500 "CDs", which allows the application to be used to create legislative
districts, too (although there is no provision for loading the old LD
polygons).

Color Opacity and Change Colors

The Color Opacity slider allows you to
change the opaqueness of the voting districts and old CD shapes. The
Change Colors button brings up a panel of
colors, allowing you to select any of the colors for any of your CDs.

Simply click on a color and the selected CD changes to that
color. Click Done Colors when you're done. Any
changes you make will be retained during your current session. You save
the current color scheme with the Save to Your Default
Colors button; this will keep your color scheme for all
future sessions. Reset to Your Default Colors
resets all colors to the colors you loaded with the session or the
colors you saved with Save to Your Default Colors during the session. Reset to Original Colors resets to the built in color scheme.

CD Panel

The rest of the controls on the left panel are related to CD information. At
the top is text showing the state's total population and a Renumber
button, which is discussed in detail below.

The remainder of the left panel is a number of rows with information
about each CD. Each row contains the following:

The number of the CD. The label Un
represents all of the unassigned districts.

A radio button, embedded in the CD's color, which is used
to select the CD you want to work on.

The total population of all the districts you have
put into the CD.

The deviation of the CD's population from the
average for the state. Your goal is to get this deviation
as close to zero as possible for all CDs.

When you select a CD, the Info Bar above the
map shows the CD's population demographics, both number of persons and
percentage, and partisan data if available.

The Renumber button allows you to renumber your
CDs. This is particularly useful after you have used a strategy to automatically
assign districts to CDs, since those strategies may have no idea which
geographic areas currently have which numbers. Once you click the button, boxes
appear on each CD row. Simply fill in the new numbers you want. Leave blank
those you don't want to change. Click Done Renumber
when you are done. The app checks to make sure you don't use duplicate numbers.
During renumbering, all other controls are disabled. Note: the colors are
still fixed to the numbers.

Top Control Panel

The top of the application has controls for
opening and saving files, selecting a state, showing various shapes and
labels, creating area views and more.

File Menu

The File Menu allows you to save and reload your work across sessions.

Save As gives you a typical Save dialog. There
is no Save to the current file, due to a limitation in Silverlight.

Close closes any loaded file and clears out
the current state.

Opengives you a typical Open dialog where you can choose a .DRF file.

Saved Files

New in Daves Redistricting 2.0, you can save your work anywhere you want. The
Save As dialog allow you to navigate to any file folder and save your .DRF file.
(The app now uses .DRF instead of .DRF.XML, even though the format is still
XML.) The .DRF stands for "Daves Redistricting File" and is simple XML to save
your work. It does not contain any state information that is loaded from the
server.

The app does cache shape and data files that are loaded from the server in Silverlight's
obfuscated folders. Also, your old saved .DRF.XML files will still be in these
obfuscated folders. Note: the new version of the app may use a
different obfuscated folder to save the cached files than the old version used
(which is where your old .DRF.XML files will be found).

On Windows, isolated storage is in hidden folders, so
you need to tell Windows to "Show Hidden Folders" (from Folder Options) to see
them.

When you begin using the new app, a Silverlight dialog box will ask you to
approve some 40 or 50 MB for isolated storage. The app asks for a bunch because
the data files from the server can be large (they have polygons). By grabbing a bunch of space the
application doesn't have to ask
again for a while.

Show

The Show section allows you to hide or show county,
or old CD boundaries, county names, city and town names, new CD labels and the
voting districts themselves. The Old/New CD check box shows the old and
new CD boundaries for the selected CD only. Cur CD shows only the
currently selected CD. Population by color views the entire
state colored according to the percentage of 3 main demographic groups (Black,
White and Hispanic); Partisan by color views the state according to partisan data, if available (2008
presidential election). The five check boxes on the right side of the Show section (with background color Bisque): Old
CDs, Cur CD, Old/New CD, Population
by color, Partisan by color, are
mutually exclusive; checking one will uncheck the others.

All labels (county, old CD, new CD, city and town names) are movable,
deletable and resizable. When you hover over a label the tool tip tells you how:
drag to move, hold the left mouse button and hit delete to delete, and hold the
left mouse button and hit 's' or 'l' to make
smaller or larger. All labels except city and town names are scaled when
zooming.

The Recalc New CD Labels button recalculates the position on the New CD
labels. Any changes you have made in size are retained.

Area Views

In the Area Views section, the Create
button creates a view of the current zoomed in area with the current Show
choices. You can create up to 70 of these. The Goto Next
button allows you to cycle through all area maps. The Goto StateView
button goes to the original view of the entire state. The Delete button deletes the current area map.

The Save View JPG
button saves the current view as a JPEG. The JPEG does not contain the Bing map in the
background, because Bing does not allow its images to be saved.

An alternative to saving a view as a JPEG is to use Print
Screen to capture the desired images and then use your favorite photo editor
(even Paint) to trim and save into a JPEG or whatever.

Automatically Assigning Districts to CDs

The app has some built-in strategies for automatically assigning districts to
CDs. The combo box labeled Auto Assign CDs allows you
to choose a strategy. One strategy simply assigns them according to the old CDs.

Another built-in strategy is to split the map into successively smaller
quadrants until small enough to begin a CD. Districts in the surrounding squares
are then assigned to the CD. This strategy does not attempt to balance the
population in the CDs are therefore is simply is a starting point.

New Population Estimates

The base data for the app is the 2000 census data. When you select the
Use New Pop Est check box, the app uses newer
population estimates. Currently these are 2008 estimates, broken down by county
and by ethnicity, from the U.S. Census Bureau. CAUTION: The app distributes the population across all
districts
in each county commensurate to the population of the districts. Therefore
splitting counties among CDs cannot be done precisely.

Find Next Unassigned

Sometimes you may think you've assigned every district to some CD, but the
Unassigned population is still non-zero. That means
some district is still unassigned. (Some can very small and easy to miss.) The
Next Unassigned button cycles through all
unassigned districts, panning and zooming to them, to help you find them.

Find CD Parts

Sometimes you may inadvertently leave a small district isolated from the rest
of the CD. The Find CD Parts button, finds separate
parts of the current CD, so you can make sure to clean them up. It uses the
bounding box (rectangle that contains a polygon) to determine if a CD has
multiple parts, so it is not guaranteed to find isolated parts of a CD,
especially in cases where the CDs are intertwined.

Other Controls

The Bump Quota button allows you to
increase the Silverlight quota for cached data files. You can also
right-click anywhere on the app to get a Silverlight menu, where you can
manage these. Help takes you to this page.
How To shows the quick "How To" screen that
appeared when you launched the app for the first time. About
tells you about the app.

Partisan Data

Partisan data, specifically 2008 presidential data, is now supported by the
application. See the LaunchApp page for a list of
which states are currently supported.

Caveats

The voting districts shapes and population data come from the
2000 census. Many states changed their voting districts between 2000 and 2008,
so the 2008 presidential data does not match completely. For Maryland, for
example, over 200 new voting districts were created during that time, so only
1600 of 1800 match the 2000 districts. The application lets you know when this
happens and then simply ignores the new districts. This could be improved if
someone is able to merge the new districts data back into the old districts.

All states that the Census Bureau provides voting
district shapes for, except New York, now support voting districts in the
application.

Help Get More Partisan Data

Find out more about partisan data and how you can help get more into the
application here.

Changes and Fixed Bugs

Version 2.0.1 improves the speed of working with the map. Now
all the districts are always shown and the speed to pan and zoom is
reasonable.

Version 2.0.2 adds the Change Colors feature and fixes Auto
Assign CDs by Quads, which was broken in 2.0.1.

Version 2.0.3 adds a caution about the lack of precision in
using new population estimates.

Version 2.0.4 adds a New Way to color districts. The Old Way is
still the default. I'm looking for your feedback via a
survey on
this and other features.

Version 2.0.5 makes New Way to color districts the default and
enables block group level new population estimates, which are much
more accurate than county level estimates.

WA has block group level new population estimates.

All New England states now support block groups, which are
much more detailed than voting districts for these states.

There was a bug loading 1.0 special test data DRF.XML into
2.0. This is now fixed (but for TX you are asked if file is
special test data).

Known issue: sometimes when you are showing Old CDs and you
zoom to level 13 or above, one of the Old CD shapes gets overlaid
where it shouldn't. Sometimes panning will make it go away. I
believe it's a bug with the Bing Map control. (See
MapPolyline Rendering Problem.)

Known issue: loading a saved .DRF for a large
state (e.g. California) can be slow, because updating the tool tips
for all of the voting districts is slow. I expect to fix this in the
near future.

Known Issue: Dragging a box to color districts
does not work on the Mac, because the Ctrl key is mapped to "Right
Mouse Button." I should be able to enable this feature with a
different key. Stay Tuned. (1/17/2011)

Credits

Except where noted, the design and implementation of this application
was created solely by me.

All of the shapes and data are from the U.S.
Census Bureau, except for the partisan data, which was put together by a few
other individuals, and the custom "special" shapes and data, which was
done by "jeffmd."